1 - Intro to Corrosion Science and Engineering

Question 1

It is a natural process that involves the deterioration of a material as a result of chemical, electrochemical or other reactions with its environment.

can occur on any material, inc metals, plastics, ceramics, and composite

Answer 1

Corrosion

Question 2

Types of Corrosion

there are 7 for this topic

Answer 2

1. Uniform Corrosion
2. Galvanic
3. Pitting
4. Crevice
5. Stress-corrosion cracking
6. Fretting Corrosion
7. Erosion-corrosion

Question 3

• This is the most common form of corrosion and occurs uniformly across the surface of a metal.
• It is often caused by exposure to moisture, chemicals, or other corrosive agents.

Answer 3

Uniform Corrosion

Question 4

occurs when two different metals are in contact with each other and there is an electrolyte (such as water) present.

Answer 4

Galvanic Corrosion

Question 5

In galvanic corrosion, the more reactive metal (________) corrodes more rapidly than the less reactive metal (________).

Answer 5

anode,cathode

Question 6

• a localized form of corrosion that creates small, deep holes or pits on the surface of a metal.
• It is often caused by the presence of aggressive chemicals or localized differences in the environment

Answer 6

Pitting corrosion

Question 7

Occurs in confined spaces, such as gaps or crevices between metal surfaces, where oxygen and other chemicals are limited.

Answer 7

Crevice corrosion

Question 8

This type of corrosion is common in seawater or other chloride-rich environments.

Answer 8

Crevice corrosion

Question 9

occurs when a metal is exposed to a corrosive environment and is under tensile stress.

Answer 9

Stress corrosion cracking (SCC)

(tensile) stress + corrosive environment = cracking

Question 10

a type of corrosion that occurs at the interface between two surfaces that are subjected to cyclic loading or vibration.

Answer 10

Fretting corrosion

Question 11

occurs when a metal surface is exposed to a corrosive environment and is also subjected to mechanical erosion, such as from flowing liquids or particles

Answer 11

Erosion-corrosion

Question 12

One of the earliest recorded instances of corrosion control comes from the ancient Egyptians to coat metal objects with a thin layer of gold or silver to protect them from corrosion.

Answer 12

Electroplating

Question 13

Used solution in electroplating

Answer 13

Gold or silver salt

Question 14

A technique which involved heating the metal to a high temperature and then quenching it in oil or water, to create a thin layer of oxide on the surface of the metal that would help protect it from further corrosion.

Answer 14

Bluing

Question 14

The technique involved placing the metal object in a solution of gold or silver salt and then passing an electric current through it to deposit a thin layer of the precious metal onto the surface

Answer 14

electroplating

Question 15

In the middle-ages blacksmiths and metalworkers would coat ________ objects with a layer of wax, oil, or tar to prevent them from rusting.

Answer 15

Iron and steel

Question 16

A major breakthrough in corrosion-resistant materials, as it contained a high percentage of chromium, which formed a protective oxide layer on the surface of the metal.

Answer 16

Stainless steel

Question 17

A corrosion resistant copper nickel alloy.

Answer 17

• Monel Metal

Question 18

Economic implication of corrosion

Answer 18

• Increase maintenance cost
• Unexpected downtime
• Increase energy consumption

Question 19

Safety implication of corrosion

Answer 19

• Compromise structural integrity
• Health risks
• Fire hazards

Question 20

In the middle-ages blacksmiths and metalworkers would coat iron and steel objects with a layer of (——), (——-), or (——-) to prevent them from rusting.

Answer 20

wax, oil, tar